The IEEE 802.16 has formulated a standard for an OFDMA mobile communication. According to the standard that is formulated by the IEEE 802.16, mobile terminals periodically transmit feedback information to a base station through a feedback channel (Feedback) of an uplink. The mobile terminals feed back information including channel quality information, information for multiple antenna transmissions, and base station selection information to the base station. On the basis of the feedback information, the base station performs packet scheduling, setting an adaptive modulation and coding scheme, setting an antenna weight in multiple antenna transmissions, and a high-speed handoff.
At this time, in order to discriminate contents that are indicated by a payload, it is required to transmit a payload that is composed of bits larger than bits that are needed to represent the payload contents.
As in the case of the multiple antenna transmissions, when a large amount of feedback information is required, a plurality of feedback channels need to be allocated to one mobile terminal.
Since a feedback channel having the same radio resource and the same data transmission rate is used regardless of a channel environment of a mobile terminal, it is not possible to efficiently use the radio resource for the feedback channel.
If the same radio resource, the same data transmission rate, and the same transmission power are used regardless of feedback types, it is not possible to apply a different function according to feedback contents.
Further, a periodic feedback channel needs to be allocated for use in feedback information from which intermittent feedback is required.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.